This project is designed to evaluate the effect of environmental chemicals on offspring of female rats subjects to totigestational exposure. Selected biochemical, histological and behavioral parameters are monitored for transplacental pathology. Three chemicals, methyl-n-butyl ketone, enflurane (ethrane), and ethchlorvynol (Placidyl), were studied initially. Postnatal effects observed were generally associated with changes in blood chemistry parameters and behavioral tests. However, these effects, although statistically significant, often lacked a dose or temporal relationship which complicated the assessment of their biological importance. There was no significant histopathology or carcinogenicity associated with any of these treatments. A more recently initiated experiment which sought to determine the possible postnatal effects associated with prenatal benzene exposure was terminated due to a mycoplasma infection outbreak in the animal colony.